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theSlotty
06-22-2001, 08:02 AM
I've noticed something odd in my openGL programs: as soon as i get near a polygon, the framerate drops rapidly. I wrote down these values:

(all that is rendered is a single quad, and two displays for fps and distance between camera and polygon)

Distance | FPS
--------------
30.0 | 230
5.0 | 200
3.0 | 170
1.0 | 100
0.1 | 90

Is that normal, or is it just my crappy graphic card (voodoo bashee)?

Or does anybody know how to speed things up there?

Tim Stirling
06-22-2001, 09:22 AM
It might be a fillrate problem, try changing screen reolution and changing the texture reolution to asses thr pixel and texel fillrates.

theSlotty
06-22-2001, 09:44 AM
the polygon isn't textured, but i tried the whole thing with a 400x300 resulotion instead of 640x480. The framerate still drops, from 300(distance: 30.0) to 190(distance: 1.0).

[This message has been edited by theSlotty (edited 06-22-2001).]

hoshi55
06-22-2001, 02:18 PM
you might be actually rendering without hardware suport, in software. that way, poly filling costs a lot of CPU time and the larger the poly gets, the more time it takes.

is the banshee an add-on accelerator or a primary card? i'm not sure about this, i own a voodoo2 which is an add-on PCI card and that thing can be a BEAST to get to work properly with your own programs... still haven't managed to get it to work under linux http://www.opengl.org/discussion_boards/ubb/frown.gif

zed
06-22-2001, 04:32 PM
fillrate (only fixs are fastercard, smaller window, less pixel calculations )

640x480
230 / 90 = 2.55
400x300 (notice the differnce is way less)
300 / 190 = 1.57

theSlotty
06-23-2001, 08:24 AM
hoshi55, its a primary card.

If i am rendering in software, how do i turn on hardware support?

zed
06-23-2001, 01:52 PM
youve defintly got hardware hardware acceleration 640x480 @230 fps is hardware. software would be 640x480 @1 fps. the problem is fillrate as u yourself have proved. fps goes up when window gets smaller.